fbsplash: use line_length instead of xres * bytes_per_pixel

In some system (e.g. my "strange" device), line_length is not equal xres *
bytes_per_pixel, so we need to use line_length in scr_fix to mmap and draw
rectangle etc.

My "strange" device output this:
bytes_per_pixel: 4
xres: 600, yres: 1024
yoffset: 0, xoffset: 0, line_length: 2432
G.addr: b74da000

Signed-off-by: Yin Kangkai <kangkai.yin@intel.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/miscutils/fbsplash.c b/miscutils/fbsplash.c
index 04d583d..988439b 100644 (file)
--- a/miscutils/fbsplash.c
+++ b/miscutils/fbsplash.c
@@ -143,7 +143,7 @@ static void fb_open(const char *strfb_device)
 
        // map the device in memory
        G.addr = mmap(NULL,
-                       G.scr_var.xres * G.scr_var.yres * G.bytes_per_pixel,
+                       G.scr_var.yres * G.scr_fix.line_length,
                        PROT_WRITE, MAP_SHARED, fbfd, 0);
        if (G.addr == MAP_FAILED)
                bb_perror_msg_and_die("mmap");
@@ -213,8 +213,8 @@ static void fb_drawrectangle(void)
        thispix = fb_pixel_value(nred, ngreen, nblue);
 
        // horizontal lines
-       ptr1 = G.addr + (G.nbar_posy * G.scr_var.xres + G.nbar_posx) * G.bytes_per_pixel;
-       ptr2 = G.addr + ((G.nbar_posy + G.nbar_height - 1) * G.scr_var.xres + G.nbar_posx) * G.bytes_per_pixel;
+       ptr1 = G.addr + G.nbar_posy * G.scr_fix.line_length + G.nbar_posx * G.bytes_per_pixel;
+       ptr2 = G.addr + (G.nbar_posy + G.nbar_height - 1) * G.scr_fix.line_length + G.nbar_posx * G.bytes_per_pixel;
        cnt = G.nbar_width - 1;
        do {
                fb_write_pixel(ptr1, thispix);
@@ -224,14 +224,14 @@ static void fb_drawrectangle(void)
        } while (--cnt >= 0);
 
        // vertical lines
-       ptr1 = G.addr + (G.nbar_posy * G.scr_var.xres + G.nbar_posx) * G.bytes_per_pixel;
-       ptr2 = G.addr + (G.nbar_posy * G.scr_var.xres + G.nbar_posx + G.nbar_width - 1) * G.bytes_per_pixel;
+       ptr1 = G.addr + G.nbar_posy * G.scr_fix.line_length + G.nbar_posx * G.bytes_per_pixel;
+       ptr2 = G.addr + G.nbar_posy * G.scr_fix.line_length + (G.nbar_posx + G.nbar_width - 1) * G.bytes_per_pixel;
        cnt = G.nbar_height - 1;
        do {
                fb_write_pixel(ptr1, thispix);
                fb_write_pixel(ptr2, thispix);
-               ptr1 += G.scr_var.xres * G.bytes_per_pixel;
-               ptr2 += G.scr_var.xres * G.bytes_per_pixel;
+               ptr1 += G.scr_fix.line_length;
+               ptr2 += G.scr_fix.line_length;
        } while (--cnt >= 0);
 }
 
@@ -254,7 +254,7 @@ static void fb_drawfullrectangle(int nx1pos, int ny1pos, int nx2pos, int ny2pos,
        cnt1 = ny2pos - ny1pos;
        nypos = ny1pos;
        do {
-               ptr = G.addr + (nypos * G.scr_var.xres + nx1pos) * G.bytes_per_pixel;
+               ptr = G.addr + nypos * G.scr_fix.line_length + nx1pos * G.bytes_per_pixel;
                cnt2 = nx2pos - nx1pos;
                do {
                        fb_write_pixel(ptr, thispix);